Biodiesel Effects on the Operation of
U.S. Light-Duty Tier 2 Engine and
Aftertreatment Systems
Marek Tatur Harsha Nanjundaswamy, Dean Tomazic
FEV Engine Technology
Matthew Thornton
National Renewable Energy Laboratory
August 15, 2007
Disclaimer and Government License This work has been authored by Midwest Research Institute (MRI) under Contract No. DE-AC36-99GO10337 with the U.S. Department of Energy (the “DOE”). The United States Government (the “Government”) retains and the publisher, by accepting the work for publication, acknowledges that the Government retains a non-exclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work or allow others to do so, for Government purposes. Neither MRI, the DOE, the Government, nor any other agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe any privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the Government or any agency thereof. The views and opinions of the authors and/or presenters expressed herein do not necessarily state or reflect those of MRI, the DOE, the Government, or any agency thereof.
Overview � Project Goals � Hardware Overview � Control System Overview � Fuel Specifications � Test Results � NOx Adsorber System � DPF Regeneration � Lean-Rich Modulation
� Vehicle Emission Test Results � Summary and Conclusions
Project Goals
� Evaluate the impact of Biodiesel fuel blends on the performance of advanced emission control systems for light-duty diesels e.g. conversion efficiencies, regeneration effects (NAC/DPF and SCR/DPF)
� Understand effects over time (system aging)
� Assess engine and fuel system operation impacts at end of project (i.e. combustion chamber, fuel injection system, fuel pump)
Hardware Overview – NOx Adsorber System
Hardware Overview – SCR System
Hardware Overview – Test Engine Hardware
400
Torque Power [HP] Power [kW]
160 160
150 150
350 140 140
130 130
300 120 120
110 110
250 100 100 To
rque
[Nm
]
90
Pow
er [k
W]
90
Pow
er [H
P]
200 80 80
70 70
150 60 60
50 50
100 40 40
30 30
50 20
10
0 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000
Engine Speed [rpm]
20
10
0
DeSOx
DeNOx
DPF Regeneration
Rapid Warm-Up
Output Module
Catalyst Protection
End of Control
Input Module
ReleaseSystem
Temperature
Lambda
Merge System
DeSOx
DeNOx
DPF Regeneration
Rapid Warm-Up
Output Module
Catalyst Protection
End of Control
Input Module
ReleaseSystem
Temperature
Lambda
Merge System
State ReleaseModule
Intervention Handler Module
ControlSystem
State ReleaseModule
Intervention Handler ModuleState Release Module
Intervention Handler Module
DeSOx
DeNOx
DPF Regeneration
Rapid Warm-Up
Output Module
Catalyst Protection
End of Control
Input Module
Release System
Temperature
Lambda
Merge System
Control System
Only used with the NOx adsorber system
NOx adsorber: Lean-rich modulation release SCR: Urea dosing
Control System Overview
Fuel Comparison
ULSD Base Fuel B20
Density (kg/dm3) 0.846 0.853
Cetane Number 42.0 43.2
Carbon (wt%) 87.08 85.04
Oxygen (wt%) 0.00 2.37
Hydrogen (wt%) 12.92 12.59
Kinematic Viscosity at 40°C [mm2/sec] 2.28 2.74
Accu
mul
ated
Soo
t [g]
0
1
2
3
4
5
6
7
8
9
10
Time [s] 0 500 1000 1500 2000 2500 3000
B20 Base Fuel
Soot
Flo
wra
te [g
/hr]
10.0
11.0
12.0
13.0
14.0
15.0
Time [s] 0 500 1000 1500 2000 2500 3000
Operating mode:
2800 rpm; 3 bar BMEP
Test Results – DPF Operation and Regeneration
DPF
Bed
Tem
pera
ture
[°C
]
200 250 300 350 400 450 500 550 600 650 700
B20 ULSD
Soot
Bur
ned
[g]
0 1 2 3 4 5 6 7 8 9
10
Time 0 50 100 150 200 250 300 350 400 450 500
Operating mode:
2500 rpm; 5 bar BMEP
Test Results – DPF Operation and Regeneration
Lam
bda
[-]
0.80 0.85 0.90 0.95 1.00 1.05 1.10 1.15 1.20 1.25 1.30 1.35 1.40
Time [s] 35 36 37 38 39 40 41 42 43 44 45
Lam
bda
[-]
0.80 0.85 0.90 0.95 1.00 1.05 1.10 1.15 1.20 1.25 1.30 1.35 1.40
B20 ULSD Lambda Setpoint
Upstream NOx Adsorber
Downstream NOx Adsorber
Operating mode:
1635 rpm; 6 bar BMEP
Test Results – NOx Adsorber Regeneration
Test Results – NOx Adsorber Regeneration
B20
10050
45 95
Thro
ttle
Valv
e D
uty
Cyc
le [%
]EG
R D
uty
Cyc
le [%
] 40
35
30
25
20
15
10
5
90
85
80
75
70
65
60
55
Post
Inje
ctio
n VN
T D
uty
Cyc
le [%
] Q
uant
ity [m
m^3
/inj]
0 50
5.0 50
4.5 45
4.0 40
3.5 35
3.0 30
25 2.5 20 2.0 15 1.5 10 1.0 5 0.5 0 0.0
35 36 37 38 39 40 41 42 43 44 45 35 36 37 38 39 40 41 42 43 44 45
Time [s] Time [s]
Test Results – NOx Adsorber Regeneration
10050
45 95
B20 ULSD
4.5 45
4.0 40
3.5 35
3.0 30
25 2.5 20 2.0 15 1.5 10 1.0 5 0.5 0 0.0
35 36 37 38 39 40 41 42 43 44 45 35 36 37 38 39 40 41 42 43 44 45
Thro
ttle
Valv
e D
uty
Cyc
le [%
]EG
R D
uty
Cyc
le [%
] 40
35
30
25
20
15
10
5
90
85
80
75
70
65
60
55
Post
Inje
ctio
n VN
T D
uty
Cyc
le [%
] Q
uant
ity [m
m^3
/inj]
0 50
5.0 50
Time [s] Time [s]
Test Results – NOx Adsorber Regeneration
CO
[%]
0
1
2
3
4
5
6
B20 ULSD
NM
HC
[ppm
]
2000
1750
1500
1250
1000
750
500
250
0
Time [s] 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55
PM [
mg/
mile
]
0 1 2 3 4 5 6 7 8 9
10 11
NOx [g/mile] 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08
Cold LA4 Hot LA4 Composite FTP75
120,000 mile Standard
50,000 mile Standard
NM
HC
[g/
mile
]
0.000
0.025
0.050
0.075
0.100
CO [g/mile] 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
120,000 mile Standard 50,000 mile
Standard
Test Results – EPA Chassis Dynamometer B20 Fuel
PM [
mg/
mile
]
0 1 2 3 4 5 6 7 8 9
10 11
NOx [g/mile] 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08
Cold LA4 Hot LA4 Composite FTP75
120,000 mile Standard
50,000 mile Standard
NM
HC
[g/
mile
]
0.000
0.025
0.050
0.075
0.100
CO [g/mile] 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
120,000 mile Standard 50,000 mile
Standard
Test Results – EPA Chassis Dynamometer ULSD
Vehi
cle
Spee
d [m
ph]
0 10 20 30 40 50 60
B20 = 11% ULSD = 10%
B20 = 46% ULSD = 45%
B20 = 43% ULSD = 45%
Accu
mul
ated
NO
x [g
]
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 Engine Out - B20
Tail Pipe Out - B20 Engine Out - ULSD Tail Pipe - ULSD
Tem
pera
ture
[°C
]
0 50
100 150 200 250 300 350 400 450 500
Time [s] 0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400
B20 - Temperature upstream LNT ULSD - Temperature upstream LNT
Test Results – EPA Chassis Dynamometer
54% 57%
96% 92%N
Ox
[g/m
ile]
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Base
EU
RO
4
T2B5
Fee
dgas
T2B5
Tai
lpip
e
0.74
0.34
0.03
0.72
0.31
0.05
B20 ULSD
Fuel
Eco
nom
y [m
pg]
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
Base
EU
RO
4
T2B5
Fee
dgas
T2B5
Tai
lpip
e
35.3 31.8 30.7
34.8 30.7 30.1
Test Results – EPA Chassis Dynamometer
Fuel
Eco
nom
y [m
pg]
25 26 27 28 29 30 31 32 33 34 35 36 37
Base
EU
RO
4
T2B5
Fee
dgas
T2B5
Tai
lpip
e
35.3
31.8 30.7
34.8
30.7 30.1
B20 ULSD
10% 12% 13% 14%
Test Results – EPA Chassis Dynamometer
289
66
356
Total CO2 emissions [g/mile]
CO2 from bio mass [g/mile]
CO2 from petro diesel [g/mile]
254 313
58 39
208 169
296
55
240
0
360 360
0
317317 209 209
0
297
0
297
ULS
D
B20
Cold
LA4
HotLA
4
HWFE
T
US06
Test Results – CO2 Contribution
Test Results – Fuel Economy Comparison
0
10
20
30
40
50
60
Mercedes C200 CDI
Audi NREL Audi A4 AV 2.0
BMW 325i Saturn Ion 2.2
Subaru Legacy
Dodge Stratus
Honda Accord
Bluetec Golf (DT) 1.9
Jetta M5 1.9
Jetta A S6 1.9
Fuel
Eco
nom
y [m
iles/
gallo
n]
City [miles/gallon] Highway [miles/gallon]
-3%
-2%
17%
27%
31%
32%
17%
27%
24%
34%
24%
32%
17%
23%
7%
16% 7%
0%
-28% -24% -21%
5%
DieselGasoline
� Vehicle as well as test cell results indicate an increase in NOx and decrease in PM using Biodiesel blends – the greater the Biodiesel portion the more pronounced is this effect. Thiseffect does not translate into greater tailpipe emissions withthe NOx adsorber aftertreatment system. � In the investigated configuration the DPF loading andregeneration performance did not change using Biodieselfuel. � NOx adsorber regeneration control remains the samecomparing petroleum based and Biodiesel blended fuel. � Fuel economy impact using Biodiesel fuel is marginal using an integrated Tier 2 Bin 5 system. � Durability investigations focusing on Biodiesel effects onengine and aftertreatment system are currently underway. � SCR system development and improvement currentlyunderway.
Summary and Conclusions
Acknowledgments DOE Office of FreedomCAR and Vehicle
Technologies, Advance Petroleum Based and Non-Petroleum Based Fuels Activities: Stephen Goguen, Kevin Stork, and Dennis Smith, Technology Managers
National Biodiesel Board: Steve Howell
MECA: Joe Kubsh and Rasto Brezny
EPA: Charles Schenk
